In a server computer utilizing a disk array, it is necessary to monitor status associated with each of multiple hard disks in the disk array and to notify a user of abnormality of the hard disks. Generally, the status associated with a hard disk can be categorized into an idle status, an access status, a fault status, an offline status and a non-present status.
Referring to FIG. 1, a conventional method for displaying status associated with storage devices such as hard disks 13 is implemented by a conventional status-monitoring device including a serial attached SCSI (SAS) controller 11, an SAS expander 12, a plurality of buffers 14 and a plurality of lighting units 15. The SAS expander 12 is electrically connected among the SAS controller 11 and the hard disks 13, and includes a plurality of sets of communication ports. Each set of communication ports includes three communication ports, two of which are electrically connected to a corresponding one of the buffers 14, and the remaining one of which is electrically connected to a corresponding one of the lighting units 15. The buffers 14 are further electrically connected to the lighting units 15, respectively.
By virtue of the SAS expander 12 that communicates with the hard disks 13 and that is operable to output a driving signal indicating the status associated with each of the hard disks 13 to one of the lighting unit 15 that corresponds to the hard disk 13 via one of the buffers 14 that corresponds to the hard disk 13, the lighting unit 15 is disabled or enabled to flash or continuously emit light. As a result, the user is notified of the status associated with each of the hard disks 13.
However, in this conventional system, each hard disk 13 requires use of three communicating ports, two of which are respectively dedicated to sending a normal status signal (either idle or access status) and a non-present status signal associated with the hard disk 13 to the corresponding lighting unit 15 through the corresponding buffer 14, and the remaining one of which is dedicated to sending an abnormal status signal (either fault or offline status) associated with the hard disk 13 directly to the corresponding lighting unit 15. That is to say, the number of the communicating ports is three times the number of the hard disks 13, which results in a relatively complicated configuration of the conventional status-monitoring device. Further, the physical circuit arrangements between each buffer 14 and the corresponding lighting unit 15 are troublesome to implement.